Ahlborn ALMEMO 2290-8, Руководство по эксплуатации

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Limit Values and Alarm
Two limit values (1 max and 1 min) can be set for each measuring channel. An
alarm value printout can be performed if a limit value is exceeded and, by
means of relay output modules, alarm contacts are provided that can be
individually allocated to limit values. As a standard, the hysteresis is set to 10
digits, however, it can also be adjusted. Furthermore, limit value exceeding can
also be used to start or stop a data logging.
Sensor Locking
All sensor data stored in the EEPROM of the connector can be protected
against undesired access by means of a graded locking function.
MEASUREMENT
A total of up to 20 measuring channels are available for 5 transducers, i.e. it is
also possible to evaluate double sensors, individually scaled sensors, or
sensors with function channels. The measuring channels can be successively
selected forwards or backwards via keyboard. The selected measuring point
can be scanned with a conversion rate of 2.5 or 10 measurements/second.
The measured value is calculated and indicated on the display or, if available,
provided on the analogue output.
Measured Value
A continuous presentation of measuring data from the selected measuring
point is provided and also includes automatic zero point correction and optional
correction of the measured value or new scaling.
A sensor breakage condition is, with most sensors, automatically detected
(exception: connectors with shunts, dividers or additional electronics).
Analogue Output and Scaling
By means of analogue start and analogue end the indicated measured value
can be scaled so that the resulting measuring range covers the full analogue
output range (2V, 10V or 20mA).
Measuring Functions
Special measuring functions are required for some sensors in order to achieve
an optimal acquisition of measuring data. The cold junction compensation is
available for thermocouples, a temperature compensation for dynamic
pressure and pH and conductivity probes, and an atmospheric air pressure
compensation for humidity sensors, dynamic pressure sensors and O
2
sensors. With infrared sensors the parameters zero point and slope correction
are used for background temperature and emissivity factor.
Maximum and Minimum Value
Each measurement involves an acquisition and storing of the maximum and
minimum value. These values can be displayed, printed or cleared.
6 ALMEMO
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2290-8
Functions